Author(s): Pak Y, Huang LC, Lilley KJ, Larner J
Abstract Share this page
Abstract We report here the in vivo conversion of [3H]myoinositol to [3H]chiroinositol. After labeling intraperitoneally with [3H]myoinositol for 3 days to reach radioisotope equilibrium in urine, [3H]chiroinositol was isolated from tissues and purified after 6 N HCl hydrolysis by two sequential paper chromatographies and high performance liquid chromatography (HPLC). Percent conversion of [3H]myoinositol to [3H]chiroinositol was highest in urine (36\%), liver (8.8\%), muscle (8.8\%), and blood (7.6\%) with intestine, brain, kidney, spleen, and heart decreasing in percentage from 2.8 to 0.7\%. Labeling of other inositol isomers including scyllo-, neo-, and epi-, and mucoinositol was minimal, approximately 0.06\% of [3H]myoinositol. Glucose was unlabeled, but glucuronate, the product of myoinositol oxidation, was labeled up to 1.5\% of the [3H] myoinositol. Acid hydrolysates of combined inositol-containing phospholipids contain significant labeled chiroinositol. [3H]Phosphatidylinositols and [3H]glycosylphosphatidylinositols were extracted from liver, muscle, and blood, isolated by thin layer chromatography, and inositols purified by HPLC after acid hydrolysis. Percent conversion of [3H]myoinositol to [3H] chiroinositol was highest in blood (60.4\%) followed by muscle (7.7\%) and liver (2.2\%).
This article was published in J Biol Chem
and referenced in Journal of Diabetes & Metabolism